The
Elizabeth Mullen Bogue Census Tract files for 1940, 1950, 1960, and
1970 were originally created by keypunching the data from the printed
publications prepared by the Bureau of the Census. The work was done
under the direction of Dr. Donald Bogue, whose wife, Elizabeth Mullen
Bogue, completed much of the data work. Subsequently, the punchcards
were converted to data files and transferred to the National Archive
and Records Administration (NARA). ICPSR received copies of these
files from NARA and converted the binary block-length records to ASCII
format.